This conference proposal is for a unique one-time only conference to be held on the subject of "Building Consensus on Qualitative Chest CT-based Subphenotypes for COPD." The conference will be held at the new American College of Radiology Education Center in Reston, Virginia. The conference will bring together thought leaders and young investigators in the field of pulmonology and radiology who have an interest in COPD. Each of these conference participants will individually read and score 140 chest CT scans from subjects who range from normal to severe COPD (GOLD Stages 0-4). Lectures and group discussions will be used to build consensus on the criteria to visually or qualitatively score chest CT scans for COPD subtypes that include the type, extent and severity of both emphysema and airway disease. The primary goals of this conference are to: 1) build consensus on how to visually read and score chest CT scans for different subphenotypes of COPD, 2) write a consensus document for the CT criteria to define COPD subphenotypes and 3) categorize and score 700 CT scans that will be placed in a public database as a resource and database for scientists and companies working to continue development in this field. This conference will be sponsored by the COPD Gene project, which will provide all of the CT scans required, and by the COPD Foundation, which is providing partial financial support and logistic support for the conference. The conference will be limited to 59 participants (the number of CT work stations available at the ACR Education Center). It will be initially open to NHLBI-supported investigators with an interest in the field of COPD and then, based on space available, open to the general scientific community. PUBLIC HEALTH RELEVANCE: This proposal is for a conference/workshop of leaders in radiology and pulmonology to develop consensus on how to visually score chest CT scans to identify clinically important different types of COPD. This conference will be held at the American College of Radiology Education Center in Reston, Virginia, and will use chest CT scans from COPD subjects created by the COPD Gene Project. Creating a consensus for the different important subtypes of COPD is a critical step in developing new therapies and personalized medicine for this major lung disease.